Several means or devices for supporting a plurality of guard cables along highways have heretofore been designed.
For example U.S. Pat. No. 1,643,123 relates to a shock absorbing highway guard comprising a series of rigid vertical supports adjacent the side of a highway and, fastened to and extending between the supports, a strip of wire fabric resistingly extensible laterally under impact.
Moreover U.S. Pat. No. 1,860,615 teaches the use of posts having affixed thereto upper and lower clips, where each clip is provided with two eyes which are adapted to receive rivots or other fastening means into the post.
U.S. Pat. No. 1,988,984 discloses the use of a strap sheet metal provided with a series of spaced loops which are adapted to connect the ends of adjacent strips or panels.
U.S. Pat. No. 2,317,249 shows the use of a plate or body member which is formed so as to provide a vertically extending outer face portion having a centrally attached bellied portion, and a clamping member which is formed so as to conform to the outer face portion upon which it is adapted to be disposed. There is formed in the clamping member a plurality of spaced apart substantially U-shaped notches into which the guard cables are adapted to be disposed where the notches are sufficiently large so as to permit relatively free movement of the guard cable therewithin after the clamping plate has been secured to the body member.
Finally U.S. Pat. No. 4,465,263 teaches the use of a web containing wires which is secured to a support by means of a securing staple. The securing staple has three semi-circular bends to accomodate the web, and also presents holes to accomodate nails which secure the staple and the web to the post such that the cables are not freely moveable relative to the staple.
Other arrangements in the prior art utilize flat spacers which include a series of vertically spaced holes which are disposed along a common line and which holes are adapted to receive U-shaped staples. Such U-shaped staples are adapted to embrace horizontally disposed cables when driven through the holes of the spacer into the wooden posts.
The highway cable clamps presently used tend to split the wooden posts particularly when the fastening means driven into the wooden posts are disposed along a common line. Split wooden posts reduce the lifetime and strength of wooden posts.
Moreover, difficulties may be encountered in quality control in driving staples or nails into the wooden posts while embracing the horizontal cables as it is not uncommon for workmen to overhammer the staple against the cable into the wooden posts so as to clamp or pinch the cable between the staples and posts. Such a condition is not desirable as the force of impact of a car against a highway guard fence constructed in such a fashion is not properly dissipated over a series of wooden posts, and it is not uncommon for a post to be prematurely sheared off because the staples do not allow the cables to be freely slidingly retained between the staple or clamp and the wooden post. The pinched cable also hinders the proper tensioning of the cable during installation and routine maintenance. The proper tensioning of the cables is necessary for maintaining the proper height of the cables from the ground.